我需要確保同時在頁面上顯示不超過 24 種產品，如果其中超過 24 種，則應該有一個按鈕，將我重定向到第二頁的產品。
也有必要， 當去下一頁， 它以某種方式反映在網站的鏈接， 即在第一頁的鏈接應該是 / 產品？PageIndex = 1， 在第二 / 產品上？PageIndex =
2 這是我的索引.html

<h1>Products</h1>

<table >
  <thead>
    <tr>
      <th>Name</th>
      <th>Price</th>
      <th colspan="3"></th>
    </tr>
  </thead>

  <tbody>
    <% @products.each do |product| %>

      <tr>
        <td><%= product.name %></td>
        <td><%= product.price %></td>
        <td><button type = 'button' class="btn btn-outline-info"><%= link_to 'Show', product %></td>
        <td><button type="button" class="btn btn-outline-success"><%= link_to 'Edit', edit_product_path(product) %></td>
        <td><button type="button" class="btn btn-outline-danger"><%= link_to 'Destroy', product, method: :delete, data: { confirm: 'Are you sure?' } %></td>
      </tr>
    <% end %>
  </tbody>
</table>
<button><%=link_to 'Destroy All', delete_all_products_path, method: :delete, data: { confirm: 'Are you sure?' } %></button>
<br>

<%= link_to 'New Product', new_product_path %>

這是我的控制器

class ProductsController < ApplicationController
  before_action :set_product, only: %i[ show edit update destroy ]

  # GET /products or /products.json
  def index
    @products = Product.all
  end

  # GET /products/1 or /products/1.json
  def show
  end

  # GET /products/new
  def new
    @product = Product.new
  end

  # GET /products/1/edit
  def edit
  end

  def count
  end

  def expensivest
    if Product.count > 0
      @product = Product.order(price: :desc)[0]
      else redirect_to products_url, notice: "Product list is empty"
    end
  end

  def median
    if Product.count > 0
      sorted = Product.order(price: :asc)
      median = sorted.length / 2
      @product = sorted[median]
      else redirect_to products_url, notice: "Product list is empty"
    end
  end

  def cheapest
    if Product.count > 0
      @product = Product.order(price: :asc)[0]
      else redirect_to products_url, notice: "Product list is empty"
    end
  end

  # POST /products or /products.json
  def create
    @product = Product.new(product_params)

    respond_to do |format|
      if @product.save
        format.html { redirect_to @product, notice: "Product was successfully created." }
        format.json { render :show, status: :created, location: @product }
      else
        format.html { render :new, status: :unprocessable_entity }
        format.json { render json: @product.errors, status: :unprocessable_entity }
      end
    end
  end

  # PATCH/PUT /products/1 or /products/1.json
  def update
    respond_to do |format|
      if @product.update(product_params)
        format.html { redirect_to @product, notice: "Product was successfully updated." }
        format.json { render :show, status: :ok, location: @product }
      else
        format.html { render :edit, status: :unprocessable_entity }
        format.json { render json: @product.errors, status: :unprocessable_entity }
      end
    end
  end

  # DELETE /products/1 or /products/1.json
  def destroy
    @product.destroy
    respond_to do |format|
      format.html { redirect_to products_url, notice: "Product was successfully destroyed." }
      format.json { head :no_content }
    end
  end

  def delete_all
    Product.delete_all
 redirect_to products_url, notice: "Product was successfully destroyed."
  end

  private
    # Use callbacks to share common setup or constraints between actions.
    def set_product
      @product = Product.find(params[:id])
    end

    # Only allow a list of trusted parameters through.
    def product_params
      params.require(:product).permit(:name, :price)
    end
end

uj5u.com熱心網友回復：

這個問題已經在這里回答了

但長話短說，你需要的是所謂的鋪墊，在鐵軌，你可以實作它與一個簡單和有效的寶石稱為卡米納里。

uj5u.com熱心網友回復：

您可以使用卡米納里或帕吉納特等幾顆寶石來實作此功能。對于此功能，無需進行自定義作業。

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